1. Field of the Invention (Technical Field)
The present invention is related to a method and device for the purification of an aqueous fluid with the application of spiral wound membrane modules, as well as a device for the implementation of this method.
2. Description of Related Art
The purification of aqueous fluids with the application of spiral wound membranes is known, mostly of the type nanofiltration or reverse osmosis (RO)/hyper-filtration, in which such membranes are arranged in series in horizontally installed pressure tubes.
Devices with spiral wound membranes that are arranged according to the state of the art in series in horizontally installed pressure tubes are often preceded by an extensive pre-treatment, in order to prevent or to limit serious pollution of the spiral wound membranes. Such pre-treatment often consists of microfiltration or ultra-filtration, if necessary combined with rapid sand filtration and/or active carbon filtration.
Apart from an extensive pre-purification, a frequent chemical purification is also applied in order to clean the spiral wound membranes. The method is according to the state of the art of longitudinal rinsing and re-circulating with water to which chemicals are added at the feeding side of the spiral wound membranes.
The device and method from Dutch patent no. 1030142 for the purification, more specifically the desalination of a fluid, more specifically with the application of a pressure tube and spiral wound membrane module, are also known.
NL 1030142 describes a device for the purification, more specifically the desalination of a fluid, in particular water with the application of a pressure tube and a spiral wound membrane module, in which inside the pressure tube several standard spiral wound membrane modules are installed in parallel and vertically.
According to the method from Dutch patent no. 1030142 a fluid, more specifically water, is desalinated, by which the fluid to be filtered is directed to a pressure tube, in which the fluid to be filtered is directed through at least two membrane modules that are arranged in parallel in the pressure tube, while creating a concentrate flow and a filtrate, and that after pollution of the membrane modules the membrane modules are cleaned hydraulically, with water and/or gas, while reversing the flow during the operation, and afterwards the method for the purification is continued again.